I've heard that many times. I'm not too young (25) so I guess it's time for me to start using anti-aging products (is it?) but is it bad for the skin if you start applying retinol or niacinamide creams when you are 18? Is it OK to use anti-aging products when your skin doesn't show any signs of aging yet (well, once you are an adult of course, or maybe it's ok for teenagers too?)?